London -LRB- CNN -RRB- -- Despite Turkey 's shelling of Syria , Middle East expert Fawaz Gerges says neither side wants an escalation of a conflict that has the potential to spill over into a regional war that would be extremely difficult to end .

It is important to stress at the outset that we do not know if the shells that landed on Turkish border towns , killing at least five people , were ordered by Bashar al-Assad 's government ; all we know is the shelling came from the area where Syrian positions had been firing at rebels .

Syria has admitted its shelling killed Turkish civilians , has apologized , and has promised that the incident will not be repeated , Turkey 's deputy prime minister says . Syria 's information minister has pledged an investigation into how and why the shell came to be fired at Turkey .

The big point is that the Assad regime is desperately trying to prevent outside military intervention in its war-torn country , and does not want to provide a pretext for Turkey to do so , knowing that it would be disastrous .

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Similarly , I believe the Turkish government has no interest in military escalation against its neighbor . According to surveys , public opinion in Turkey is strongly against all-out war with Syria .

Equally important is the fact that , although NATO and the United States have expressed solidarity with Turkey , a NATO member , they are urging restraint . Western powers , particularly the United States , do not have the desire or political will to intervene militarily in Syria . Without the full backing of NATO and the US , Turkish Prime Minister Erdogan would be reluctant to embark on any large-scale military venture against Syria .

So while we have seen a lot of escalation in the last 48 hours we need to put it into context : Neither side has an interest in turning this low-intensity war into something more serious , a full-blown confrontation .

What the incident tells us is that Syria has now descended into all-out war . It tells us that Syria 's neighbors are deeply embroiled in its internal armed struggle . It also tells us that the civil war has become a proxy war between other regional players such as Iran and Saudi Arabia . The Syrian conflict has also been internationalized along Cold War lines , with the US and Russia backing rival camps .

The spillover of the Syrian war has reached not just Turkey but also Jordan , Lebanon , and Iraq , with frequent armed clashes and casualties . If these skirmishes intensify and escalate , the potential of a region-wide war can not be overlooked .

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This is why Western powers , particularly the United States , are reluctant to intervene militarily in the Syrian civil war , lest they exacerbate an already dangerous situation : They want the civil war to remain an internal conflict where it can be contained .

Al-Assad 's strategy has succeeded : He has forced the opposition to militarize the political uprising . Syria is in the grip of a bloody and costly armed struggle , a struggle that does not show signs of an early resolution , but of turning into a long , drawn-out conflict . No one knows how that would end , but it would ensure he has local and regional support to survive for quite a long time .

The Syrian authorities have little control over all military engagements . The fire has spread across the whole country : Assad 's forces are over-extended and thinly spread . Despite assurances given by the Syrian government that the shelling that killed the Turkish civilians wo n't be repeated , it is doubtful whether that pledge can be honored as Syria descends into all-out war .

Turkey has been extremely angry in the last few weeks . For the first time Prime Minister Recep Tayip Reccip Erdogan has criticized the Western powers for paying lip service to the opposition cause , implying that his patience is running thin .

Regardless of how the Turkish leadership feels though , I do n't think it will act independently without a security umbrella commitment by NATO and a green light from the Americans . They have made it very clear they will not act on their own against Syria . NATO has gone out of its way to impress gently on the Turkish leadership not to escalate the situation beyond what it has done so far .

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Syrian shells hit towns across the border in Turkey , killing at least five

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Syria apologizes for incident , says it will not be repeated

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Fawaz Gerges says neither side wants Syria 's civil war to spread across region